Question

Where do antigens come from?

Answer 1

Antigens may originate from within the body or from the external environment.

Answer 2

Antigens are proteins that are found on the surface of the pathogen.Antigens are unique to that pathogen. The whooping cough bacterium, for example, will have different antigenson its surface from the TB bacterium. When an antigen enters the body, the immune system produces antibodies against it.